In vitro interaction of human HDL with human apolipoprotein A-II. Synthesis of apolipoprotein A-II-rich HDL.
The aim of this study was to define the specific affinity of human apolipoproteins A-I and A-II for HDL lipids and to investigate the possible transfer of apolipoproteins from the HDL molecule. For this purpose we incubated human HDL with increasing amounts of isolated apolipoprotein A-II. After incubation the reaction products were separated by gel chromatography and apolipoproteins A-I and A-II were quantified separately by immunonephelometry and HDL lipids by thin-layer chromatography. According to our results, apolipoprotein A-II progressively displaces apolipoprotein A-I to generate an HDL-like particle with identical lipid composition, hydrodynamic properties and lipid fluidity. These data indicate that apolipoprotein A-II is able to displace quantitatively apolipoprotein A-I from HDL in vitro, and that such a mechanism might contribute to the regulation of the HDL2 in equilibrium or formed from HDL3 distribution in plasma.
D016632:Apolipoprotein A-I; D016633:Apolipoprotein A-II; D001053:Apolipoproteins / Q000378:metabolism*; D001667:Binding, Competitive; D002850:Chromatography, Gel; D002855:Chromatography, Thin Layer; D006801:Humans; D008075:Lipoproteins, HDL / Q000096:biosynthesis*
D016632:Apolipoprotein A-I; D016633:Apolipoprotein A-II; D001053:Apolipoproteins; D008075:Lipoproteins, HDL